The invention relates to a modular central electrical unit for motor vehicles, comprising an electrically insulating base body having plug locations, which are formed on the outer wall of the base body, for accommodating an electrical and an electromechanical functional unit, which plug locations are connected to one another and to a cable harness and/or an electronic functional unit.
The relays and/or plugs and fuses required for a specific vehicle equipment level are combined in a central electrical unit. Separate cable harnesses lead from here to various controllers, switches and actuators.
Such a central electrical unit essentially carries out a distributor function, in order to supply electrical voltage to the electrical loads in the motor vehicle, such as the windshield wipers or flashers, via electrical cables or cable harnesses, and to monitor the serviceability of the loads. The electrical loads are in this case actuated via relays, which are arranged together with the fuses for the load circuits, plugged in the top face of the central electrical unit.
DE 42 27 182 C1 discloses a central electrical unit in which a basic body is formed from a plurality of partial base bodies, with the partial base bodies being electrically connected to one another via a relay. This has the disadvantage that the central electronics unit cannot be disassembled until the plugs and relays have been removed. Furthermore, cable-harness plugs cannot be plugged on and made contact with individually until the central electronics unit has been fitted.
All the plug lots (possibly as well as contacts) which may be required for the maximum equipment level must be reserved during the production of the central electrical unit. Variants which go beyond the scope, once it has been defined, or changes to individual plug-in locations can be provided only by redesign and replacement of the complete relay base, and this is feasible only with major effort.
The invention is thus based on the object of specifying a central electrical unit which can be expanded and/or modified without any additional space requirement.
According to the invention, the object is achieved in that an electrical connection which passes out of the base body, or base module, is such that it overhangs the base body, and a base body segment, or auxiliary module, which is formed from a plug-in body of a vehicle component that is to be connected, is mechanically attached to the base body, as a modular construction, with the base body segment and/or the fitted functional unit being electrically connected to the electrical connection.
The advantage of the invention is that, while retaining a single basic body or module which is used for standard vehicle functions, a specific number of design variants can be reserved from any desired number of options, without having to define this completely even before vehicle introduction. In this case, there is no need to reserve the physical space for all possible variants, some of which are mutually exclusive. The plug-in locations for reception of the vehicle components to be connected are such that the vehicle components can be fitted as partial segments, namely, the auxiliary modules, to the base module, there being additional plug-in locations for additional electronics.
In one refinement, on its surface, the base body segment has plug-in locations for a relay and/or a fuse and/or a mating connector for an electronic functional unit.
In a development of the invention, the base body segment is formed from the plug body of a cable-harness plug.
In this case, the plug bodies form autonomous partial segments, which are latched to the base body when fitted, and enlarge it piece by piece. Both individual components such as relays or fuses as well as complete controllers (for example a central electronics unit) can be plugged individually and directly onto these flexibly expandable building blocks, without any additional wiring.
The electrical connection is advantageously a distribution rail which is fitted with supply voltage lines and to which all the additional base body segments can be electrically connected. The electrical, electronic and/or electromechanical functional units which are connected to the base body segments can easily make contact with the distribution rail with the aid of electrical means arranged on the base body segment.
In addition to the lines for the supply voltage, bus lines for networking the individual components with one another and for networking the individual components with external devices are also advantageously formed on the distribution rail. Such a rail with supply and communication lines is used not only for networking but also to further reduce the wiring complexity.
The distribution rail can be produced particularly easily if it is in the form of a sheet-metal stamping.
In one refinement, the base body segments can be made contact with on both sides of the distribution rail.
In one refinement, the distribution rail overhangs the base body centrally, with base body segments being mechanically attached to the base body on both sides of the distribution rail, and with the cable harnesses of said base body segments being connected to various external electrical or electronic devices.
A second base body segment is advantageously attached to the first base body segment, and makes electrical contact with the distribution rail. The base body segments are in this case self-supporting.
A more robust arrangement is achieved if a frame for accommodating a base body segment is arranged on the base body and encloses the distribution rail, which passes out of the base body. The frame in this case forms an expansion area, which can be used as required, for various assemblies.
The base body and the frame are advantageously formed integrally. This is easy to achieve using a plastic injection-molding method.
The robustness can be further improved if a functional unit makes contact with the base body and a partial body segment or two partial body segments, engaging around them.